Assignment 3:
Important Notes:
1) Only assignments answered in assignment form will be accepted.
2) Due date for handing in Assignment3 is Wednesday 12/12/2012.
Handing in the assignments : locker 15, 3rd floor.
The German University in Cairo
Faculty of Information Engineering & Technology
Electronics Department
Electronics and Communications 9
Photonics (Elct 901)
Fall 2012
th
semester
Assignment 3
Problem 1:
Find the phase retardation for light normally incident on a ¯42m crystal with an electric field
E applied along a cubic axis. Let L be the thickness of the crystal. Assume the field is applied
in a direction orthogonal to the propagation direction.
Problem 3:
A linearly polarized electromagnetic wave at ¸ = 6328°A is incident normally at x = 0 on the
yz face of a quartz crystal so that it propagates along the x axis (so-called “x -cut”). Suppose
the wave is polarized initially so that it has equal components along y and z.
a) What is the state of polarization at the plane defined by the x- coordinate where
(kz - ky)x = π/2.
b) A plate which satisfies the condition in (a) is known as a quarterwave plate because the
difference in the phase shift for the two orthogonal polarization states is a quarter of 2 π. Find
the thickness of a quartz quarter-wave plate at λ = 6328°A.
c) What is the state of polarization at the plane defined by the x-coordinate, where 2π/ λ (nen0) x = π.
Problem 3:
The crystal lithium niobate (LiNbO3) belongs to the 3m crystal symmetry class. The ordinary
and extraordinary indices of refraction are (in zero field) no = 2.272 and ne = 2.187
respectively. The nonzero electro-optic coefficients are r33 = 30.8 × 10-12; r13 = 8.6 × 10-12;
r22 = 3.4×10-12and r51 = 28×10-12 m/V. The electro-optic matrices are given by:
investigate what happens if we apply an E field along the x-direction. Write down the
ellipsoid equation and find the corresponding impermeability tensor.